The desirability of applying elastic in the waist areas of various types of garments to assist in fitting of the garments is well known. The traditional method of securing elastic to a garment is by sewing the elastic to the garment material. The material is either gathered and the elastic is applied in a relaxed condition or the material is maintained flat and the elastic is applied in a stretched condition. The sewing of the elastic to the garment material, whether the sewing is done by hand or by machine, is slow and therefore costly in terms of the labor required.
In relatively modern technology relating to disposable garments, elastic strip material has been bonded to sheet material by the use of adhesives or heat bonding. These approaches have been commercially successful where the elastic strips have been applied with their lengths in the direction of movement of the sheet material from which the garment is formed. However, efforts to apply elastic strip material with all or a portion of its length transverse to the direction of movement of the garment sheet material have not been as successful. Examples of these approaches are illustrated in Rega U.S. Pat. No. 4,285,747 and Bourgeois U.S. Pat. No. 3,828,367. The Rega patent discloses the application of an unstretched elastic strip to a continuously moving web in a direction transverse to the direction of movement of the web and across a longitudinal tuck in the web. After application of the strip to the web, the web is extended in the lateral direction to remove the tuck and stretch the strip so that the web is elasticized in the area of the strip. In the Bourgeois patent, continuous elastic ribbon in a stretched condition is fed into grooves in a roll. The grooves are disposed in a direction transverse to the direction of a continuous web moving under the roll. As the web moves under the roll, the stretched elastic is applied to the web to elasticize the web in the areas of the ribbon.
In another area of prior art relevant to the present invention, apparatus has been developed for rotating strip material and applying it to sheet material in a direction transverse to the direction of movement of the latter. Also, apparatus has been developed for rotating objects from one orientation to another while the objects are moving from a receiving station to a delivery station of the apparatus. U.S. Pat. Nos. 3,728,191 to Wierzba et al and 4,394,898 to Campbell disclose examples of these types of apparatus. The Wierzba patent relates to the attaching of an adhesive tape to a web which ultimately forms part of a disposable diaper. The tape is used to fasten the waist of the diaper. An endless length of the tape material is continuously fed onto a platen mounted on a revolving roll. A strip of the tape is cut from the endless length by a cutting blade which engages the tape and an anvil mounted on the frame of the roll. The platen is rotated by a cam drive mechanism utilizing a cam surface mounted separately from the roll on the frame of the apparatus. The platen rotates the severed strip while carrying it to a transferring station where the strip is applied to a web with the length of the strip transverse to the direction of movement of the web.
In the Campbell patent, a series of diapers are fed onto rotatable platens mounted on a continuously revolving roll. Alternating ones of the platens are rotated 90.degree. in opposite directions so that alternating diapers carried by the platens are correspondingly rotated. The alternately rotated diapers are carried on the platens and delivered to a receiving conveyor. The platens are rotated by a cam drive mechanism having a cam control surface mounted externally of the revolving roll in a stationary manner on the frame of the apparatus.
A problem with the apparatus disclosed in the Wierzba patent is that, due to the force of the cutting blade against the tape and the anvil on the frame of the roll, the severed end of the tape strip may be temporarily welded to the anvil. The extent of the welding problem will depend in part on the material characteristics of the tape, e.g., the flexibility and softness or brittleness of the tape material. The consequence of the welding of the tape strip to the anvil is that, upon rotation of the platen and the strip, the strip will not rotate with the platen and will be moved laterally out of place due to its severed end remaining welded to the anvil on the frame. The cam drive arrangements of the Wierzba and Campbell patents require, particularly where the roll and the platen are moving at relatively high speeds, lubrication of the cam surface used to control the drive means. The material carried by the roll will consequently be exposed to the dirt and grime which commonly accompanies lubricants.
The applicant's invention is an improvement over the apparatus of the Wierzba and Campbell patents and, in particular, over the apparatus disclosed in the Wierzba patent.